Security devices using light are known.
In U.S. Pat. No. 6,007,218 a laser based security device is shown that uses visual laser light at predetermined wavelengths and intensities to create temporary visual impairment to cause hesitation, delay, distraction and reductions in combat and functional effectiveness.
In U.S. Pat. No. 6,190,022 a visual security device is shown that uses sequentially flashing multiple LEDs.
The references listed herein also provide background.